A Brief Review of H2S and Nitrogen-Based Contaminants from Biogas: Effects on Reforming Catalysts and SOFC Anodes.

This paper provides a brief review of biogas contaminants, examining the impact of hydrogen sulfide (H2S), nitrogen (N2), and ammonia (NH3) on catalytic reforming processes and Solid Oxide Fuel Cells (SOFCs) electricity generation. Biogas, produced through anaerobic digestion (AD), is a promising renewable energy source that can be upgraded into biomethane and reformed into H2-rich syngas for SOFCs. Despite this, contaminants like H2S found in biogas and biomethane cause critical issues such as catalyst poisoning, decreased electrochemical performance, and higher maintenance costs, while NH3, potentially formed from N2 during reforming, can lead to catalyst degradation and reduced SOFC performance, representing an underexplored contamination pathway. This review highlights the negative impacts of H2S, N2, and NH3 on catalytic reforming and SOFCs, causing catalyst deactivation and performance loss, thus reinforcing the importance of developing advanced purification methods and sulfur-tolerant materials to improve renewable hydrogen (H2) production and fuel cell durability.